Proximal Stones Research Articles

A Multicenter Comparison of the Safety and Effectiveness of Ureteroscopic Laser Lithotripsy in Obese and Normal Weight Patients

Surgical treatment of kidney stones in an obese patient (body mass index [BMI] >30 kg/m(2)) remains challenging as shockwave lithotripsy may not be an option due to weight limitations. We sought to determine the effectiveness of ureteroscopic laser lithotripsy in obese patients compared to nonobese controls. Patients from 2004 to 2007 were retrospectively analyzed providing a group of 292 patients (163 obese, 76 overweight, 53 normal) who underwent ureteroscopic procedures for urolithiasis at four centers in the United States and Canada. The percentage of obese patients requiring flexible ureteroscopy (URS) (79%) was higher than in the other groups (P<0.0001). Flexible URS was associated with a lower stone-free rate (SFR) on multivariate analysis (P=0.034). There was no difference in SFRs of patients who required a ureteral access sheath, basket extraction, or received a postoperative stent. Complication rates did not differ between groups. SFRs using ureteroscopic lithotripsy in obese and overweight populations are the same as in the normal weight patients. A flexible ureteroscope was associated with a decreased SFR, but this likely due to a more proximal stone location in these patients. Ureteroscopic laser lithotripsy is an effective and safe technique to treat urolithiasis in the overweight/obese patient.

Emergency double-J stent insertion following uncomplicated Ureteroscopy: risk-factor analysis and recommendations

Emergency double-J (DJ) stenting following ″uncomplicated″ ureteroscopic (UURS) stone treatment is both morbid and costly. Our study aims at identifying those patients who are more likely to require such an extra procedure. Handling of this complication will also be highlighted. 319 cases of UURS cases were selected out of 903 patients, who were admitted for URS stone treatment at King Abdullah University Hospital during the period from May, 2003 to December, 2010. Thirty-eight of them (11.9%) had emergency post-URS DJ stenting within 24 hours of discharge. The medical records of all UURS cases were retrospectively reviewed. Comparison in demographic and stone-related variables was made using 2-paired t-test with P < 0.05. Operative findings of 38 stented patients were outlined. Significant risk factors for emergency stenting were noted in males with larger (> 1.5 cm) and proximal stones (38 stented vs. 281 unstented). Operative risk factors among the 38 patients were: initial procedure time > 45 minutes (42.1%), ureteral wall edema (21.1%), repeated access for stones > 1.5 cm (21.1%), impacted stone (10.5%) and ignored or missed stones/fragments (4.6%). The need for emergency DJ stenting following UURS stone treatment is not uncommon. The routine insertion is impractical and weakly-supported. With risk-factor stratification, selective and individualized DJ stenting policy is recommended.

Effect of ureteric stone location on the success rate of ureteroscopic Holmium laser lithotripsy

Background: Ureteral stone can cause obstructive uropathy and subsequent deterioration of renal function. There are four treatment options for ureteral calculi: lithotripsy, ureteroscopy, laparoscopic ureterolithotomy, and open stone surgery. Holmium YAG laser is an excellent intracorporial lithotripter for all kinds of stones. Accordingly, there is steady increase in number of ureteroscopic laser lithotripsy operations in the managmant of Ureteral stone.&#x0D; Objectives: this study was designed to demonstrate the effect of ureteric stone location on the success rate of ureteroscopic Holmium laser lithotripsy in the management of ureteric stones.&#x0D; Patients and Methods: Ninety middle-aged patients of either sex (35.9 ± 10.8 years) with ureteric stone (9.5 ± 3 mm) were treated with semiregid ureteroscopy using Holmuim: YAG laser as an intracorporial lithotripter. In 32 patients (35%) the stone were located in the lower ureter, 22 patients (24%) in middle ureter and in 36 patients (40%) in the upper ureter. Then all the patients were followed up on day 1 and 4 weeks for clearance of stone by plain abdominal radiography and abdominal ultrasonography.&#x0D; Results: the stone free rates 4 weeks after the treatment were 66% for upper, 75 % for middle and 87.5% for lower ureteric stones. In 12 patients (13%)cannot be possible to reach the stone, six patients (6.6 %) had proximal stone migration and treated later on by extracorporeal lithotripsy after double-J stent placement. Ureteral perforation occurred in 7 patients (7.7%), all managed by double-J stent placement except 1patient needed an open surgical treatment..&#x0D; Conclusion: YAG laser lithotripsy is efficacious modality of treatment for ureteric stones especially in lower ureter and it is a safe and technically feasible and in early experience, it is preferred to start with more distal stones.

1676 RADIATION EXPOSURE OF THE PATIENT SUBMITTED TO ENDOUROLOGIC TREATMENT FOR URETERAL CALCULI

You have accessJournal of UrologyStone Disease: SWL, Ureteroscopy or Percutaneous Stone Removal (II)1 Apr 20131676 RADIATION EXPOSURE OF THE PATIENT SUBMITTED TO ENDOUROLOGIC TREATMENT FOR URETERAL CALCULI Filippo Nigro, Paolo Ferrarese, Giuseppe Benedetto, Enrico Scremin, Emiliano Bratti, Sergio Savastano, and Andrea Tasca Filippo NigroFilippo Nigro Vicenza, Italy More articles by this author , Paolo FerraresePaolo Ferrarese Vicenza, Italy More articles by this author , Giuseppe BenedettoGiuseppe Benedetto Vicenza, Italy More articles by this author , Enrico ScreminEnrico Scremin Vicenza, Italy More articles by this author , Emiliano BrattiEmiliano Bratti Vicenza, Italy More articles by this author , Sergio SavastanoSergio Savastano Vicenza, Italy More articles by this author , and Andrea TascaAndrea Tasca Vicenza, Italy More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.3038AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Patients treated for ureteral calculi are at risk to receive high levels of ionizing radiation during their clinical state. We measured the total amount of radiation exposure for a group of patients affected by ureteral stones, from the onset of their symptoms to the conclusion of their clinical fate. METHODS Monocentric retrospective study including 64 patients submitted in 2010 to ureterorenoscopy (URS) for ureteral calculi, localised at pielo-ureteral junction (13 cases, 20% - group 1), lumbar tract (22 cases, 35% - group 2), pelvic tract (16 cases, 25% - group 3), ureterovesical junction (13 cases, 20% - group 4). All 64 patients underwent abdominal X-ray (KUB) and ultrasonography (US); 49 patients (77%) required an additional CT scan to improve the diagnosis. The total amount of radiation exposure from the onset of symptoms, during endourologic treatment, to 3 months of follow up was measured, using Gray (Gy), the unit of the absorbed dose, and Sievert (Sv), expressing the equivalent dose, i.e. the stochastic biological effects of ionizing radiation. The measured data were related to location and volume of the stones. RESULTS Stone size was homogeneous in all groups (mean 0,8 mm); mean fluoroscopy time during URS was 116 seconds (s) (group 1), 172 s (group 2), 78 s (group 3), 83 s (group 4), observing less time of radiation exposure (p < 0,05) for distal (pelvic and prevesical) than proximal (pielo-ureteral and lumbar) stones. This result was confirmed after correction for stone size. In addition, the absorbed dose was significantly lower (p < 0,05) in groups 3 and 4 [mean for groups 1-4 expressed in milliGray (mGy): 1) 8,915; 2) 9,451; 3) 4,878; 4) 4,744]. 56 patients (88%) were evaluated 2 months after treatment with KUB and abdominal US, 8 patients (12%) required a CT scan to achieve the diagnosis. Mean measured exposure radiation was: 19mSv (group 1), 21msV (group 2), 15mSv (group 3), 15 mSv (group 4). CONCLUSIONS The total radiation received by the studied population was lower than 50 mSv, the recommended dose limit in a year for workers according to International Commission on Radiological Protection. This is the first report concerning the measurement of total amount of radiation a patient submitted to URS for ureteral stone receives in his clinical fate. The use of fluoroscopy during endourological procedures increases patient's radiation exposure and adds to all radiological diagnostic examinations. It's critical that endourologist is sensitised to this problem in order to minimize the employ of ionising radiation during endourological treatment. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e689-e690 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Filippo Nigro Vicenza, Italy More articles by this author Paolo Ferrarese Vicenza, Italy More articles by this author Giuseppe Benedetto Vicenza, Italy More articles by this author Enrico Scremin Vicenza, Italy More articles by this author Emiliano Bratti Vicenza, Italy More articles by this author Sergio Savastano Vicenza, Italy More articles by this author Andrea Tasca Vicenza, Italy More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Categorization of intraoperative ureteroscopy complications using modified Satava classification system

To review our experience with ureteroscopy (URS) in the treatment of ureteral calculi and stratify intraoperative complications of URS according to the modified Satava classification system. We performed a retrospective analysis of 1,208 patients (672 males and 536 females), with a mean age of 43.1 years (range 1-78), who underwent ureteroscopic procedures for removal of ureteral stones. Intraoperative complications were recorded according to modified Satava classification system. Grade 1 complications included incidents without consequences for the patient; grade 2 complications, which are treated intraoperatively with endoscopic surgery (grade 2a) or required endoscopic re-treatment (grade 2b); and grade 3 complications included incidents requiring open or laparoscopic surgery. The stones were completely removed in 1,067 (88.3%) patients after primary procedure by either simple extraction or after fragmentation. The overall incidence of intraoperative complications was 12.6%. The most common complications were proximal stone migration (3.9%), mucosal injury (2.8%), bleeding (1.9%), inability to reach stone (1.8%), malfunctioning or breakage of instruments (0.8%), ureteral perforation (0.8%) and ureteral avulsion (0.16%). According to modified Satava classification system, there were 4.5% grade 1; 4.4% grade 2a; 3.2% grade 2b; and 0.57% grade 3 complications. We think that modified Satava classification is a quick and simple system for describing the severity of intraoperative URS complications and this grading system will facilitate a better comparison for the surgical outcomes obtained from different centers.

320 Evaluation of a novel fascial dilator modified with scale marker in PCNL for reduction of x-ray exposure: A randomized clinical study

0,8 mm); mean fluoroscopy time during URS was 116 seconds (s) (group 1), 172 s (group 2), 78 s (group 3), 83 s (group 4), observing less time of radiation exposure (p 0,05) for distal (pelvic and prevesical) than proximal (pielo-ureteral and lumbar) stones. This result was confirmed after correction for stone size. In addition, the absorbed dose was significantly lower (p 0,05) in groups 3 and 4 [mean for groups 1-4 expressed in milliGray (mGy): 1) 8,915; 2) 9,451; 3) 4,878; 4) 4,744]. 56 patients (88%) were evaluated 2 months after treatment with KUB and abdominal US, 8 patients (12%) required a CT scan to achieve the diagnosis. Mean measured exposure radiation was: 19mSv (group 1), 21msV (group 2), 15mSv (group 3), 15 mSv (group 4). CONCLUSIONS: The total radiation received by the studied population was lower than 50 mSv, the recommended dose limit in a year for workers according to International Commission on Radiological Protection. This is the first report concerning the measurement of total amount of radiation a patient submitted to URS for ureteral stone receives in his clinical fate. The use of fluoroscopy during endourological procedures increases patient’s radiation exposure and adds to all radiological diagnostic examinations. It’s critical that endourologist is sensitised to this problem in order to minimize the employ of ionising radiation during endourological treatment.

Simultaneous saline irrigation during retrograde rigid ureteroscopic lasertripsy for the prevention of proximal calculus migration.

In this paper, we analyze the clinical efficacy of a simultaneous saline irrigation method in treating upper-mid ureteral stone migration and evaluate its effectiveness during ureteroscopic lasertripsy. We prospectively evaluated 78 patients with a total of 95 upper-mid ureteral stones, which were treated with holmium:YAG lasertripsy. These patients were randomized into 2 groups. In Group 1 (39 cases with 44 ureteral stones), conventional ureteroscopic lasertripsy was performed. In Group 2, (39 cases with 51 ureteral stones), the simultaneous saline irrigation method was used during lasertripsy. There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by spiral computed tomography or excretory urography. Data were analyzed regarding stone migration, lengths of time, and ureteral clearing for various stages of each procedure. One patient in Group 2 (2%) experienced upward stone migration, while this occurred in 8 patients in Group 1 (20%). The operative time in Group 1 ranged from 35 to 55 minutes (mean: 44.8 ± 5.3), while in Group 2 it ranged from 40 to 69 minutes (mean: 50.4±3). There was no significant different in the operative times between the two groups (p < 0.05). Ureteral perforation, urinoma and urosepsis were not seen in both groups. The simultaneous saline irrigation method demonstrated a statistically significant advantage over conventional methods. The operation can be performed persistently under clear vision, and since the stones cannot move upward, fragmented portions are easily flushed out. Our data suggest that this method is simple, safe and effective in preventing proximal stone migration during ureteroscopic lasertripsy.

Management of Sialolithiasis of Submandibular Gland: Sialendoscopy-Assisted Intraoral Stone Removal

Background and Objectives Intraoral removal is one of the most common treatments for sialolithiasis, and although newly introduced, sialendoscopy is becoming a popular tool for it. The aim of this study was to investigate the factors that influenced the removal of sialolithiais by sialendoscopy and also to compare its usefulness with intraoral removal alone. Subjects and Method We retrospectively reviewed surgical results of 89 patients who underwent therapeutic sialendoscopy and compared them with the result of 43 patients who underwent intraoral removal without sialendoscopy between June 2006 and February 2012. We analyzed the success rate of sialendoscopy for sialolithiasis by age, location, stone size, stone shape and stone mobility. Then we compared sialendoscopy-assisted intraoral removal group with intraoral removal alone group by location, size and mobility. Results Among the total 89 patients with sialolithiasis of submandibular gland who underwent sialendoscopy-assisted intraoral removal, 47 were successfully treated by therapeutic sialendoscopy alone (52.8%), and 84 by sialendoscopy-assisted intraoral removal (94.3%). In cases of proximal stones and those larger than 5 mm in size, sialendoscopy-assisted intraoral removal (95.0%) was more successful than intraoral removal alone (30%). The mean operation time (min) for sialendoscopy was 39 min and that for intraoral removal after sialendoscopy was 43 min. Sialendoscopy- assisted intraoral removal took 82 min and intraoral removal alone took 56 min. Conclusion Results of sialendoscopy assisted stone removal supports the less invasive therapy of proximal stones via intraoral route. We thus recommend considering sialendoscopic approach prior to considering other approaches.

Economic Outcomes of Treatment for Ureteral and Renal Stones: A Systematic Literature Review

We evaluated the cost-effectiveness of ureteral/renal stone treatment by comparing ureteroscopy, extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy. We performed a systematic literature search to identify studies of treatment for adults with ureteral and renal stones that were published between 1995 and 2010. For inclusion in analysis studies had to provide the stone-free rate and the cost of at least 2 therapies. Ten studies were identified, including 8 with an observational design and 2 that synthesized data using decision modeling techniques. Five of 6 studies, including 1 of 2 from the United States, compared ureteroscopy vs shock wave lithotripsy for proximal stones and showed a higher stone-free rate and lower cost for ureteroscopy. Four of the 5 studies, including the only American study, compared ureteroscopy vs shock wave lithotripsy for distal ureteral stones and also showed such an economically dominant result. Studies of shock wave lithotripsy vs percutaneous nephrolithotomy and ureteroscopy vs percutaneous nephrolithotomy for renal stones demonstrated higher cost and a higher stone-free rate for percutaneous nephrolithotomy. Despite the great heterogeneity and limited quality of available cost-effectiveness evaluations most studies demonstrated that ureteroscopy was more favorable than shock wave lithotripsy for ureteral stones in stone-free rate and cost.

Risk Factors for Post-ERCP Cholangitis in Patients with Pancreatic Cancer from a Single Referral Center in Iran

Cholangitis is relatively uncommon but associated mortality is high due to the predisposition in people with underlying disease. For this recognition of contributing risk factors is necessary. Therefore, the present descriptive- analytical cross-sectional survey was designed to determine contributing risk factors for post-ERCP cholangitis in patients with pancreatic cancer. From 2005 to 2010, 110 consecutive cases of pancreatic cancer attending to a tertiary referral centre (Taleghani Hospital), Tehran, Iran were recruited. The patients all underwent stenting via endoscopic retrograde cholangiopancreatography (ERCP). On univariate analysis, a metallic stent type (95% confidence interval (CI) 1.025-11.34, P=0.037), having no jaundice (1.44-2.22, P=0.009), having no pain (1.32-1.91, P=0.026), a history of prior ERCP (1.16-10.37, P=0.020), and having a proximal biliary stone (1.002- 5.93, P=0.046) were related to cholangitis. However on multivariate analysis, none of these factors were found to be contributing risk factors. Cholangitis is avoidable with adequate biliary drainage. Because success rates are higher and complication rates lower for endoscopists performing large volumes of ERCP, performance of the procedure should be concentrated as much as possible in institutions with endoscopists having adequate experience. Patients with a high risk for complications may be best served by referral to an advanced center.

1035 The experience of mini-PCNL in the treatment of large impacted proximal ureter stones

1035 The experience of mini-PCNL in the treatment of large impacted proximal ureter stones

Fragmentation without extraction in ureteral stones: outcomes of 238 cases

We aimed to evaluate the success rates, auxiliary procedures and complications after ureteroscopic lithotripsy (URS) during which the fragments left in situ for spontaneous passage after complete disintegration into a acceptable (<4 mm) size. 238 patients with ureteral stones were treated with URS between 2005 and 2011, and disintegrated fragments (<4 mm) were left in situ for spontaneous passage. Patients were followed with radiography for 3 months and evaluated with respect to the success rates (stone-free), auxiliary procedures, complication rates and additional analgesic requirement. The median age was 42.2 ± 13.7 years, and overall stone size was 8.79 ± 2.94 mm. Significantly lower rate of stone-free status was achieved in proximal stones (p < 0.05). A second URS was necessary in 5% (n = 12) of the patients. Double-J catheter placement during initial URS did not cause any change in the rate of secondary URS (p = 0.620). Additional oral or intramuscular analgesia was required in 41% (n = 97) and 25% (n = 59) of the patients, respectively, after discharge. The overall stone-free rate was 95% and mean time to complete clearance was 5 days. Severe colic pain within 24 h was noted in 21 (9%), and transient hydro-ureteronephrosis in 31 (13%) patients, as minor complications. Leaving the fragments (<4 mm) in place for spontaneous passage following a successful disintegration in URS could be a reasonable approach with acceptable and comparable stone-free rates, and this approach appears to give chance of shortening the duration of operation and also avoiding from the potential morbidity of repeated manipulations during the both further disintegration and extraction.

Safety and efficacy of ureteroscopic pneumatic lithotripsy.

To determine the safety and efficacy of ureteroscopic pneumatic lithotripsy (PL) for the clearance of ureteral calculi (UC). Experimental study. Department of Urology, KRL Hospital, Islamabad, from March 2006 till December 2008. Ureteroscopic PL was performed on 104 patients with ureteric calculus measuring > 6 mm; using Swiss Lithoclast through a 9.5 French semi-rigid ureteroscope. At the end of the procedure, a DJ stent was inserted. Complications were noted. Stone clearance was assessed through X-ray KUB. DJ stent was removed within 3 - 6 weeks after the procedure. Sixty-eight patients (65.4%) were males and 36 (34.6%) females. The average hospital stay was 2.6 + 2.8 days; 72 (69.6%) patients were discharged on the first post-procedure day. Complete stone clearance was achieved in 98 (94.2%) patients, at 3-6 weeks. Four patients (26.7% of upper ureteral stones) had stone retropulsion. The only major complication was perforation occurring in 2 (1.9%) distal ureters. One case was successfully managed by endoscopic DJ stent placement, the other required open repair. Ureteroscopic PL is effective in clearing majority of middle and distal UC. Patients with proximal stones may have stone retropulsion. Ureteric perforation is an uncommon complication.

A comparison of Stone Cone versus lidocaine jelly in the prevention of ureteral stone migration during ureteroscopic lithotripsy.

Intracorporeal lithotripsy modalities and stone removal devices have been created to facilitate endoscopic management of ureteral stones. These devices, along with improved techniques, have resulted in stone-free rates greater than 95% with low morbidity. However, problems remain that preclude consistent 100% stone-free rates with endoscopic treatment of ureteral calculi. Retrograde migration during ureteroscopic procedures remains a significant problem. The aim of this study was to compare the Stone Cone device and instillation of lubricating lidocaine jelly as two methods to prevent retrograde stone migration during ureteroscopic lithotripsy. This study included patients suffering from ureteral stones that were treated with intracorporeal lithotripsy using the pneumatic Lithoclast. These patients were divided into two groups. In group I, the Stone Cone device was used, while in group II, lidocaine jelly 2% concentration was used. This study included 40 patients with a mean age of 38.6 ± 9.3 years (20 patients in each group). There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by excretory urography. The pneumatic Lithoclast allowed successful fragmentation of all calculi into small fragments. Upward stone migration did not occur in patients in the Stone Cone group, while in the lidocaine jelly group it occurred in three patients (15%). The operative time in the Stone Cone group ranged between 30 and 55 minutes (mean, 41.8 ± 5.3), while in the lidocaine jelly group it ranged between 40 and 71 minutes (mean, 51.4 ± 3.4), and this difference was statistically significant (p < 0.05). The Stone Cone is safe and efficient in preventing proximal stone migration during ureteroscopic pneumatic lithotripsy. It maintained continuous ureteral access and demonstrated a statistically significant advantage over the lidocaine jelly in terms of proximal stone migration, operative time, and the need for auxiliary procedures.

E136 Effect of tamsulosin on ureter function in patients with proximal and distal stones in the upper urinary tract

E136 Effect of tamsulosin on ureter function in patients with proximal and distal stones in the upper urinary tract

Causes of renal forniceal rupture

What's known on the subject? and What does the study add? Renal forniceal rupture is a common finding in patients with ureteral obstruction. It is thought to be due to increased renal pelvis pressure from backup of urine, causing one or more renal fornices to leak urine. This phenomenon has not been systematically studied. Herein we retrospectively review the causes and associated clinical findings in over 100 cases of renal forniceal rupture. • To perform a retrospective review aiming to identify causes of renal forniceal rupture. • A retrospective review was performed of the longitudinal medical record and CT records for patients identified as having renal 'forniceal rupture' or 'calyceal rupture' using a radiological database. • In total, 108 patients were identified with the CT diagnosis of renal 'forniceal' or 'calyceal' rupture. • Forniceal rupture was caused by ureteric stones in 80 cases (74.1%), malignant extrinsic ureteric compression in nine cases (8.3%), benign extrinsic ureteric compression in two cases (1.9%), pelvic-ureteric junction obstruction in two cases (1.9%), vesico-ureteric junction (VUJ) obstruction in one case (0.9%), bladder outlet obstruction in one case (0.9%) and iatrogenic causes in four cases (3.7%). • No definitive cause was found in nine cases (8.3%). For patients in whom a ureteric stone was the cause of forniceal rupture, the level of obstruction was proximal ureter in 24.3% of cases, distal ureter in 17.6% of cases and VUJ in 58.1% of cases. • Mean (sd) stone size was 4.09 (2.0) mm. Mean (sd) stone size was 5.34 (1.87) mm for proximal stones, 4.08 (1.69) mm for distal stones and 3.53 (1.96) mm for VUJ stones (P= 0.005). • Urinary tract infection was present in five out of 97 patients (5.2%) in whom data were available for analysis. • The most common aetiology of renal forniceal rupture is obstruction caused by distal ureteric stones followed by malignant extrinsic ureteric compression.

Editorial Comment

The authors share their experience of treating large proximal ureteral stones using semirigid ureteroscopes and a pneumatic lithotripter. At first glance, it would appear that overall they achieved remarkably outstanding stone-free rates. However, there was a 20% rate of failed initial ureteroscopy (7% in women, 35% in men), which is not surprising given the fact that the authors were using large-diameter (8-13.5 F) instruments. The higher failure rate in men is not surprising and reflects the fact that the male lower urinary tract anatomy at times is just not suited for ureteroscopy of the proximal ureter. The mere fact that 80% of the time the proximal stone was accessed is a testament to the expertise of the authors in performing semirigid ureteroscopy. Semirigid Ureteroscopy in Management of Large Proximal Ureteral Calculi: Is There Still a Role in Developing Countries?UrologyVol. 77Issue 5PreviewTo evaluate the outcome and complications of the use of semirigid ureteroscopy (URS) together with intracorporeal pneumatic lithotripsy in the management of upper ureteral calculi >10 mm in diameter. Full-Text PDF ReplyUrologyVol. 77Issue 5PreviewWe share the same opinion as the editors that if flexible instruments and holmium laser lithotripsy were available, they would be the first choice in the management of large proximal ureteric stones. However, we all know how expensive the cost of such equipment is in developing countries, making them available only in extremely selected institutes. We offer semirigid ureteroscopy to patients, knowing that we would expect a failure rate, to spare them the other alternative, open surgery. As the editors' state, “… the higher failure rate in men is not surprising and reflects the fact that the male lower urinary tract anatomy at times is just not suited for ureteroscopy of the proximal ureter.” Full-Text PDF

Stress waves in kidney stones.

A 3‐D time‐domain finite‐difference solution to the linear elastic equations was applied to investigate the stress and velocity fields of kidney stones subject to lithotripsy shock waves. The kidney stone models were scanned from micro‐computed tomography and had diameters from 2 to 5 mm. It was found for these shapes that shear waves induced by interference of the shock wave with stone boundaries dominated the high stress in the stones. The traditional belief of stone comminution mechanism by spall mechanism does not play important role due to the irregular proximal and distal stone surfaces. It was found for natural stones that stone orientation had an impact on the generation of high stress with a smooth convex surface producing the highest internal stresses. The results indicate that lithotripters with a focal width larger than a stone should be able to break a stone more efficiently since the large focal width shock waves result in stronger interaction with stone circumferences and produce larger she...

1946 CONTEMPORARY PRACTICE PATTERNS IN SURGICAL MANAGEMENT OF STONE DISEASE

You have accessJournal of UrologyStone Disease: New Technology/SWL, Ureteroscopic or Percutaneous Stone Removal1 Apr 20111946 CONTEMPORARY PRACTICE PATTERNS IN SURGICAL MANAGEMENT OF STONE DISEASE Michael Childs, Laureano Rangel, James Lingeman, and Amy Krambeck Michael ChildsMichael Childs Rochester, MN More articles by this author , Laureano RangelLaureano Rangel Rochester, MN More articles by this author , James LingemanJames Lingeman Indianopolis, IN More articles by this author , and Amy KrambeckAmy Krambeck Rochester, MN More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2127AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Shock wave lithotripsy (SWL) is the most common surgical procedure for stone disease despite the efficacy of ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL). Factors influencing treatment selection for stone disease have not been well evaluated. We assessed treatment preferences for stone disease and identified factors associated with treatment selection. METHODS Electronic surveys were sent to urologists with American Medical Association membership. After selecting a treatment modality for clinical stone scenarios, information was obtained on training, practice, equipment ownership, and clinical factors related to treatment. Survey results were assessed for factors associated with treatment selection. RESULTS Of 600 surveys, 200 were initiated and 180 completed. Additional endourologic training was reported in 29%(55/189). Academic practice (AP) and community practice (CP) were reported in 33%(63/189) and 64%(121/189). High volume stone practices (>100 cases/year) were more likely in CP vs AP (57.8% vs 36.5%, p<0.001). High volume SWL practice was more likely in CP (6.7% vs 1.6%) while high volume URS (19% vs 11.4%) and PCNL (3.2% vs 0%) practices were more common in AP (p<0.001). Time since training was associated with treatment selection for all renal and proximal stones. PCNL and URS were preferred with fewer years since training while SWL was preferred with increasing time since training (p<0.03). Lithotriptor ownership was associated with SWL preference over URS or PCNL for proximal urolithiasis (<5mm to 15mm), renal pelvis and upper pole nephrolithiasis (<5mm to 15mm) and lower pole nephrolithiasis (<5mm to 10mm) (p<0.01). Most trends for SWL preference were independent of urologist age on multivariate analysis. Holmium laser ownership and lithotriptor availability did not influence treatment selection (p>0.05). Clinical factors important in stone treatment selection (stone size, location, composition, age, comorbidities, bilaterality, surgical schedule, or payer status) did not differ based on equipment ownership or time since training (p>0.05). CONCLUSIONS Stone treatment selection preference varied by practice type, with high volume SWL practice in CP and high volume URS and PCNL practice in AP. PCNL and URS were preferred with less time since training and SWL preferred with increasing time since training. Furthermore, lithotriptor ownership was associated with SWL selection over URS or PCNL while lithotriptor availability and holmium laser ownership were not. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e778 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Michael Childs Rochester, MN More articles by this author Laureano Rangel Rochester, MN More articles by this author James Lingeman Indianopolis, IN More articles by this author Amy Krambeck Rochester, MN More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

The Impact of Proximal Stone Burden on the Management of Encrusted and Retained Ureteral Stents

Managing the encrusted and retained ureteral stent is a potentially complex challenge. To improve surgical planning, we hypothesized that proximal stone burden is the most important factor associated with complicated removal, and that computerized tomography more accurately estimates stone burden than plain film x-ray of the kidneys, ureters and bladder. Records were reviewed of patients undergoing surgical removal of an encrusted and retained ureteral stent or nephrostomy at Ben Taub General Hospital from 2007 to 2009. Preoperative imaging consisted of a plain x-ray of the kidneys, ureters and bladder and/or computerized tomography of the abdomen/pelvis. Each encrusted tube was assessed using the FECal (forgotten, encrusted, calcified) grading system and associated stone burden was calculated. Univariate and multivariate analyses were performed to determine factors associated with the need for multiple surgeries. A total of 55 encrusted and retained ureteral stents and 1 nephrostomy were removed from 52 patients. Mean tube duration was 24.9 months. Most tubes were removed endoscopically (94.2%). Of the patients 21.2% required multiple surgical procedures to remove each tube. Computerized tomography graded stone burden more accurately than plain x-ray of the kidneys, ureters and bladder (94.9% vs 64.4%, p = 0.01). Plain x-ray of the kidneys, ureters and bladder underestimated proximal stone burden in 44.4% of patients who underwent multiple surgeries. When dividing stone burden into 3 categories (0 to 100, 101 to 400 and greater than 401 mm(2)) only proximal stone burden correlated with multiple surgeries and surgical complications (p = 0.01 for both). On multivariate analysis only proximal stone burden was associated with multiple surgeries to remove each tube (OR 12.1, 95% CI 1.5-95.9, p = 0.02 for 101 to 400 mm(2) and OR 18.1, 95% CI 1.7-192.8, p = 0.02 for greater than 401 mm(2)). In patients with encrusted and retained ureteral stents accurate determination of the proximal stone burden, preferably by computerized tomography, is important for surgical counseling and planning.